Seeds Expiry Date

It's all do do with the type of seed and how you keep them! Keep them in a fridge and they will last longer, but certain seeds last longer than others!
What seeds are they?

If it's any help, the seeds are
Tomatoes (Sweet Million F1 & Marmande & The Love Apple)
Strawberry (Sarian F1 & Mignonette)
Brussels Sprouts (Peer Gynt F1)
Broccoli (Autumn Spear)
Leeks (Musselburgh)
Florence Fennel (Sirio)
Cucumber (Marketmore)
Lettcue (Little Gem)
Baby Aubergine (The Stripy Egg Plant)

Tomatoes should be all right from my experience. In fact, at just one season over the recommendation they are all likely to be OK. Some seeds are more sensitive than others, I believe carrot seed doesn't keep.

Parsnips are thought to be the worst keepers - but you don't have any of those.

I think the way you keep them is the most important thing. Air tight container, cool place. Unfortunately, you don't know how they have been kept by their previous owner.

Perhaps its me, but I could have sworn that my shop-bought seeds (kept warm and packets exposed to the light) haven't done as well as that from mail-order, over the years.

The best advice I have is to use them as soon as you can!

Get hold of a copy of "The Vegetable Expert" by Dr Hessayon. Excellent reference book, if a bit dated now. Gives you recommended planting distances, expected yield, and life expectancy of seed. Seed viability also depends on correct storage, of course, cool dry and dark is favourite.

The life expectancy is different in every book or article you read, unfortunately.

If you have lots of seeds, then try germinating a dozen or so on moist paper in a warm place... that will give you a reasonable idea of whether the batch is viable or not.

If you have very few seeds, then do the best you can to give them the perfect conditions and have some more seeds on standby, just in case.

Thanks for all your useful replies. One thing for sure, I will try and start using the seeds between now and early next year. If they germinate, I'll continue to use any remaining seeds in 2009. I'll just continue using them until they no longer germinate. In the process, I'll note down seeds viability for each vegetable over a period of time so that I have a record for future reference. This will be a useful experiment in itself.

Probably not relevant but the RHA germinated some seeds recently 200 years old

You can always try a few on damp kitchen paper a week or so before you intend to sow them, just to check viability. Mr Flum and his Dad once found a tin of elderly seed packets which had belonged to Grandad. Many of them came. They had an allotment at the time so gave over a small bed to the old stuff, just to see. The brassica family fared best - we had some cracking turnips - golden ball, really hot & spicy!

It's been updated now The Vegetable and Herb Expert. Still a great reference book.

Are you stalking me Two Sheds?
We seem to be answering these in tandem this morning! What a team! (What ? A team???)

Yes I agree, the mail order ones are perhaps better than shop bought that have been exposed to light for too long. Imagine how worse the car boot sale ones would be, exposed to direct sunlight!!!
May freeze them to help stop deteriorate any further, any faster.

Yes I read that too recently. Incredible! Maybe I shouldn't be too worried.

Thanks Flummery, encouraging story.

Been researching on the Net and this is what I've come up with in case anybody's interested in storing their seeds for longer life.

The shorted lived seeds tend to be Carrot, Parsnip, Leek, Onion, Spinach, Beet and some herbs, may remain viable between 6 months and 2 years...I don't know but it sounds like mostly Root and Onion/allium family vegetables.

They say Cauliflower seeds can last between 3 to 4 years depending on variety. Some variety may only last for 1 year. I think Flummery is right, the Brassicas are tough old birds for seeds.

Tomoto, pepper, aubergine, cucumber, cucurbits and bean seeds can easily remain viable for 4-5 years if kept dry at room temperature.

Keeping seeds in fridge or freezer can substantially prolong the seed life (even more so for freezer) but this may be more relevant if one lives in a very hot & humid country. However beware of frost free models of fridge/freezer, they dehydrate the seeds by sucking the moisture out of them. For your precious heirloom seeds, freezer may offer you a peace of mind over a much longer period of time...over 10 years possibly???

To store seeds in fridge/freezer, make sure you keep them inside an airtight, moisture-proof container such as a glass jar with an airtight lid. Also while planting out, never leave seed packets lying around in the sun or let them get wet.